• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.2
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• pp.207-218
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• 2001

The purpose of this study was to investigate the direct inhibitory effect of calcium hydroxide materials on differentiation and activation of osteoclast. we used the osteoclast progenitor cells isolated from bone marrow cell of chick embryo tibia and four experimental materials [$Ca(OH)_2$ powder, Metapaste$^{(R)}$, Vitapex$^{(R)}$, Pulpdent$^{(R)}$] diluted at 0.1, 0.01, $0.05{\mu}g/ml$. There were measured both the number of differentiated osteoclast and the area of resorption lacunae. Also, we conducted MTT assay on U2OS osteoblast to examine of cytotoxic effect and obtained following result. 1. Considering the result of the inhibitory effects upon osteoclast differentiation, There were shown a significant difference increased in the following order: Metapaste$^{(R)}$, $Ca(OH)_2$ powder, Vitapex$^{(R)}$. But no significant difference was found in pulpdent group that the number of differentiated osteoclast was increased at all concentrations(p<0.05). 2. Among the three experimental groups, that is, $Ca(OH)_2$ powder, Metapaste$^{(R)}$, Vitapex$^{(R)}$ at $0.1{\mu}g/ml$ dilution that were statistically significant in reduction of the number of differentiated osteoclast. Vitapex group showed significant cytotoxic effect compared to control and another two groups exhibited no significant difference. Also, 0.2% DMSO group was shown statistically siginificant cytotoxicity (p<0.05). 3. Examining pattern and measured area of resorption lacunae in the control and the three experimental groups ,that is, $Ca(OH)_2$ powder, Metapaste$^{(R)}$, Vitapex$^{(R)}$ at $0.1{\mu}g/ml$ dilution, except $Ca(OH)_2$ powder group, statistically significant differences were found between experimental groups and control group. Also, DMSO group showed statistically significant decrease (p<0.05). From these results, we think that calcium hydroxide is responsible for suppression of hard tissue resorption by a direct inhibition of dfferentiation and activation of osteoclast.

• Journal of Nutrition and Health
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• v.51 no.6
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• pp.498-506
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• 2018

Purpose: Lycopene, a carotenoid with anti-oxidant properties, occurs naturally in tomatoes and pink grapefruit. Although the beneficial effects of lycopene on various disorders have been established, little attention has been paid to the possible anti-diabetic effects of lycopene focusing on ${\beta}$-cells. Therefore, this study investigated the potential of lycopene to protect ${\beta}$-cells against apoptosis induced by a cytokine mixture. Methods: For toxicity experiments, the cells were treated with 0.1 ~ 10 nM of lycopene, and the cell viability in INS-1 cells (a rat ${\beta}$-cell line) was measured using a MTT assay. To induce cytokine toxicity, the cells were treated with a cytokine mixture (20 ng/mL of $TNF{\alpha}$ + 20 ng/mL of IL-$1{\beta}$) for 24 h, and the effects of lycopene (0.1 nM) on the cytokine toxicity were measured using the MTT assay. The expression levels of the apoptotic proteins were analyzed by Western blotting, and the level of intracellular reactive oxidative stress (ROS) was monitored using a DCFDA fluorescent probe. The intracellular ATP levels were determined using a luminescence kit, and mRNA expression of the genes coding for anti-oxidative stress response and mitochondrial function were analyzed by quantitative reverse-transcriptase PCR. Results: Exposure of INS-1 cells to 0.1 nM of lycopene increased the cell viability significantly, and protected the cells from cytokine-induced death. Lycopene upregulated the mRNA and protein expression of B-cell lymphoma-2 (Bcl-2) and reduced the expression of the Bcl-2 associated X (Bax) protein. Lycopene inhibited apoptotic signaling via a reduction of the ROS, and this effect correlated with the upregulation of anti-oxidative stress response genes, such as GCLC, NQO1, and HO-1. Lycopene increased the mRNA expression of mitochondrial function-related genes and increased the cellular ATP level. Conclusion: These results suggest that lycopene reduces the level of oxidative stress and improves the mitochondrial function, contributing to the prevention of cytokine-induced ${\beta}$-cell apoptosis. Therefore, lycopene could potentially serve as a preventive and therapeutic agent for the treatment of type 2 diabetes.

• Journal of Life Science
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• v.28 no.8
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• pp.908-916
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• 2018

Hair loses melanin with aging, which leads to hair graying. The change in hair color is caused by a reduction in tyrosinase activity and an accumulation of hydrogen peroxide ($H_2O_2$) in hair follicles. The purpose of this study was to investigate the effect of ethanolic extract of Oryza sativa (OREE) on melanin production and antioxidative activity in B16F1 cells. In this study, OREE showed low DPPH radical scavenging activity and reducing power. However, it displayed a strong antioxidative effect against intracellular $H_2O_2$ in live cells. OREE did not inhibit DOPA oxidation activity in vitro, but it increased tyrosinase activity at a concentration of $64{\mu}g/ml$. OREE at a concentration higher than $32{\mu}g/ml$ showed cell toxicity in B16F1 cells. However, OREE at a concentration higher than $8{\mu}g/ml$ not only increased melanin synthesis in a dose-dependent manner in B16F1 cells but also increased melanin synthesis in cells treated with $H_2O_2$ inhibiting melanin synthesis. To confirm the effect of OREE on melanin production, Western blot analysis was performed. The results revealed that OREE increased the expression levels of tyrosine hydroxylase and tyrosinase-related protein-2 (TRP-2) involved in melanin production in the $H_2O_2$-treated cells in which melanin production was inhibited. The findings suggest that OREE could improve melanin synthesis and be available for development of hair cosmetics aimed at improving melanin production.

• The Journal of Korean Obstetrics and Gynecology
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• v.19 no.4
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• pp.61-76
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• 2006

Purpose : This study examined the non-toxic and the anti-oxidative effect of Dioscoreae Rhizoma on PC12 cells. Sanyak(Dioscoreae Rhizoma; chinese yam, shan yao) is well-known for its curing power for kidney, lung, spleen. Tonifies and augments the spleen and stomach. Tonifies the lung gi and augments the kidney yin. Tonifies the kidneys and also stabilizes and binds. it also binds the essence and treats spermatorrhea, frequent urination, and vaginal discharge. We are therefore interested in whether Dioscoreae Rhizoma is capable of causing abnormal apoptosis processes, and whether this condition can be rectified through Dioscoreae Rhizoma herb treatment. Methods : We used aqueous extract to treat PC12 cells with different concentrations treated with a water or a MeOH extract of Dioscoreae Rhizoma (0, x10, x20, x40, x80). The MTT (3, (4, 5-dimethyl-thiazol) 2, 5-diphenyl-tetraxolium bromide) reduction assay was employed to quantify the differences in cell activity and viability. The Bax expression level was monitored using western-blotting techniques. The patterns of the changes in expression were scanned and analyzed. Results : Bax and GSK-3${\beta}$ promotes cell death and down-regulated during the development of the PC12 cells. This is indicated that Dioscoreae Rhizoma is capable of inducing apoptosis in PC12 cells. The induced cell death and significantly inhibited by Dioscoreae Rhizoma, which can be explained by the increase in the inhibition of Bax and GSK-3${\beta}$ expression. It was also shown that Dioscoreae Rhizoma inhibits the release of $H_2O_2$ and prevents lipid peroxidation. Furthermore, the accumulation of wild type Bax protein significantly downregulated in a dose-dependent manner upon treatment with Dioscoreae Rhizoma. Conclusion : In conclusion, Dioscoreae Rhizoma can induce apoptosis via a Bax-dependent pathway or GSK-3${\beta}$ dependent pathway in PC12 cells into anti-oxidant and protective effect.

• Journal of Life Science
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• v.13 no.1
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• pp.118-127
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• 2003

$\rho$-Fluorophenylalanine (FPA), a phenylalanine analog, is able to induce apoptotic cell death of human acute leukemia Jurkat T cells. To better understand the mechanism by which FPA induces apoptotic cell death, the effect of ectopic expression of antiapoptotic proteins, Bcl-2 and Bcl-xL, on FPA-induced apoptosis was investigated by employing lurkat T cells transfected with Bcl-2 gene (JT/Bcl-2) or Bcl-xL gene (1/Bcl-xL) and Jurkat T cells transfected with vector (JT/Neo or J/Neo). When Jurkat T cells, JT/Neo or J/Neo, were exposed to FPA at concentrations ranging from 0.63 to 5.0 mM, the cell viability determined by MTT assay declined in a dose-dependent manner. In addition, apoptotic DNA fragmentation along with several apoptotic events such as caspase-8 activation, Bid cleavage, mitochondrial cytochrome c release, caspase-9 activation, caspase-3 activation, and degradation of PARP was induced. However, the FPA-induced cytotoxic effect, activation of caspase-8, and cleavage of Bid were significantly abrogated by ectopic expression of Bcl-2 or Bcl-xL. At the same time, there was marked reduction in the level of cytochrome c release from mitorhondria, caspase-9 activation, caspase-3 activation, and degradation of PARP. These results indicate that caspase-8 activation, Bid cleavage, and mitochondrial cytochrome c release with subsequent activation of the caspase cascade are negatively regulated by Bcl-2 or Bcl-xL, and are thus required for FPA-induced apoptosis in Jurkat T cells

• Journal of Oriental Neuropsychiatry
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• v.21 no.2
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• pp.125-140
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• 2010

Objectives : The purpose of this study is to examine from various angles the protective effect of Gastrodia elata Blume (GEB) against nerve cell death induced by $\beta$-amyloid by using the cell line SH-SY5Y, which is commonly utilized for toxicity testing in nerve cells, and to find out its mechanism of action. Methods : To begin with, as a result of assessing the rate of cell survival by employing MTT reduction assay, the treatment with $\beta$-amyloid at different concentrations caused cytotoxicity, which was inhibited by preprocessing GEB extract. In addition, after $\beta$-amyloid was processed with the cell SH-SY5Y, apoptosis progressed, which was reduced effectively by processing GEB extract. Results : When cytotoxicity was caused by using hydrogen peroxide, a representative ROS, in order to examine the antioxidant effect of GEB, its protective effect was also observed. Apart from ROS, reactive nitrogen species (RNS) are also known to play a crucial role in nerve cell death. The treatment with the NO donor SNAP increased the production of nitric oxide and the expression of iNOS, which was also inhibited by GEB extract. Meanwhile, as an attempt to find out the mechanism of action explaining the antioxidant effect, the intracellular antioxidant enzyme expressions were measured by RT-PCR, which showed that GEB extract increased the expressions of heme oxygenase-1, GAPDH and $\gamma$-glutamate cysteine ligase. Lastly, GEB extract had a protective effect against impaired memory induced by scopolamine in animal models (in vivo). Conclusions : These findings indicate that GEB has a protective effect against the death of cranial nerve cells, suggesting possibilities for the prevention and treatment of AD.

• Molecules and Cells
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• v.24 no.1
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• pp.95-104
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• 2007

The mechanism of acacetin-induced apoptosis of human breast cancer MCF-7 cells was investigated. Acacetin caused 50% growth inhibition ($IC_{50}$) of MCF-7 cells at $26.4{\pm}0.7{\mu}M$ over 24 h in the MTT assay. Apoptosis was characterized by DNA fragmentation and an increase of sub-G1 cells and involved activation of caspase-7 and PARP (poly-ADP-ribose polymerase). Maximum caspase 7 activity was observed with $100{\mu}M$ acacetin for 24 h. Caspase 8 and 9 activation cascades mediated the activation of caspase 7. Acacetin caused a reduction of Bcl-2 expression leading to an increase of the Bax:Bcl-2 ratio. It also caused a loss of mitochondrial membrane potential that induced release of cytochrome c and apoptosis inducing factor (AIF) into the cytoplasm, enhancing ROS generation and subsequently resulting in apoptosis. Pretreatment of cells with N-acetylcysteine (NAC) reduced ROS generation and cell growth inhibition, and pretreatment with NAC or a caspase 8 inhibitor (Z-IETD-FMK) inhibited the acacetin-induced loss of mitochondrial membrane potential and release of cytochrome c and AIF. Stress-activated protein kinase/c-Jun $NH_4$-terminal kinase 1/2 (SAPK/JNK1/2) and c-Jun were activated by acacetin but extracellular-regulated kinase 1/2 (Erk1/2) nor p38 mitogen-activated protein kinase (MAPK) were not. Our results show that acacetin-induced apoptosis of MCF-7 cells is mediated by caspase activation cascades, ROS generation, mitochondria-mediated cell death signaling and the SAPK/JNK1/2-c-Jun signaling pathway, activated by acacetin-induced ROS generation.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6191-6196
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• 2012

Aims and Background: Traditional chemotherapy strategies for human leukemia commonly use drugs based on cytotoxicity to eradicate cancer cells. One predicament is that substantial damage to normal tissues is likely to occur in the course of standard treatments. Obviously, it is urgent to explore therapies that can effectively eliminate malignant cells without affecting normal cells. Our previous studies indicated that ginsenoside $Rg_1$ ($Rg_1$), a major active pharmacological ingredient of ginseng, could delay normal hematopoietic stem cell senescence. However, whether $Rg_1$ can induce cancer cell senescence is still unclear. Methods: In the current study, human leukemia K562 cells were subjected to $Rg_1$ exposure. The optimal drug concentration and duration with K562 cells was obtained by MTT colorimetric test. Effects of $Rg_1$ on cell cycle were analyzed using flow cytometry and by SA-${\beta}$-Gal staining. Colony-forming ability was measured by colony-assay. Telomere lengths were assessed by Southern blotting and expression of senescence-associated proteins P21, P16 and RB by Western blotting. Ultrastructural morphology changes were observed by transmission electron microscopy. Results: K562 cells demonstrated a maximum proliferation inhibition rate with an $Rg_1$ concentration of $20{\mu}\;mol{\cdot}L^{-1}$ for 48h, the cells exhibiting dramatic morphological alterations including an enlarged and flat cellular morphology, larger mitochondria and increased number of lysosomes. Senescence associated-${\beta}$-galactosidase (SA-${\beta}$-Gal) activity was increased. K562 cells also had decreased ability for colony formation, and shortened telomere length as well as reduction of proliferating potential and arrestin $G_2$/M phase after $Rg_1$ interaction. The senescence associated proteins P21, P16 and RB were significantly up-regulated. Conclusion: Ginsenoside $Rg_1$ can induce a state of senescence in human leukemia K562 cells, which is associated with p21-Rb and p16-Rb pathways.

• The Journal of Internal Korean Medicine
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• v.31 no.1
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• pp.54-65
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• 2010

Objective : The water extract of Chungsimyeonja-eum (CSYJE) has traditionally been used in treatments of heart diseases and brain diseases in Oriental medicine. However, little is known about the mechanism by which CSYJE protects neuronal cells from injury damages. Therefore, in this study we attempted to elucidate the mechanism of the cytoprotective effect of the CSYJE extract on glutamate-induced C6 glial cell death. Methods : Cultured cells were pretreated with CSYJE and exposed to glutamate, cell damage was assessed by using MTT assay and propidium iodide (PI), probe 2',7'-dichlorofluorescein diacetate (DCF-DA) staining. Western blotting was performed using anti-procaspase-3 and anti-PARP, respectively. Result : We determined the elevated cell viability by CSYJE extract on glutamate-induced C6 glial cell death. Glutamate induced DNA fragmentation on C6 glial cells but pre-treatment with CSYJE inhibited DNA fragmentation. One of the main mediators of glutamate-induced cytotoxicity was known to generation of reactive oxygen species (ROS). Pre-treatment with CSYJE inhibited this ROS generation from glutamate-stimulated C6 glial cells. Also, we identified that the ROS-induced DCF-DA green fluorescence was reduced by CSYJE pre-treatment. The critical markers of apoptotic cell death are the cleavages of procaspase-3 protease and PARP proteins, so we checked the expression level and cleavages of procaspase-3 protease and PARP proteins. Glutamate-treated C6 glial cells showed the cleavages of procaspase-3 protease and PARP proteins and followed the reduction of expression of these proteins. Conclusion : These findings indicate that CSYJE may prevent cell death from glutamate-induced C6 glial cell death by inhibiting the ROS generation and procaspase-3 and PARP expression.

• Journal of Periodontal and Implant Science
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• v.32 no.3
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• pp.665-683
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• 2002

A novel glucanhydrolase from a mutant of Lipomyces starkeyi KSM 22 has additional amylase activity besides mutanolytic activity and has been suggested as promising anti-plaque agent. It has been shown effective in hydrolysis of mutan, reduction of mutan formation by Streptococcus mutans and removal pre-formed sucrose-dependent adherent microbial film and has been strongly bound to hydroxyapatitie. These in vitro properties of Lipomyces starkeyi KSM 22 glucanhydrolase are desirable for its application as a dental plaque control agent. In human experimental gingivitis　model and 6 month clinical trial, mouthrinsing with Lipomyces　starkeyi KSM 22 dextranase was comparable to 0.12% chlorhexidine mouthwash in inhibition of plaque accumulation and gingival inflammation and local side effect was negligible. This study was aimed to evaluate the cytotoxic effect of Lipomyces starkeyi KSM 22 glucanhydrolase on human gingival fibroblasts. Primary culture of human gingival fibroblasts at the 4th to 6th passages were used. Glucanhydrolase solution was made from lyophilized glucanhydrolase powder from a mutant of Lipomyces stakeyi KSM 22 solved in PBS and added to DMEM medium to the final concentration of 0.5, 1, and 2 unit. Cells were exposed to glucanhydrolase solution or 0.1 % chlorhexidine and the cells cultured in DMEM with 10% FBS and 1% antibiotics as control. After exposure, the morphological change, cell attachment, and cell activity by MTT assay were evaluated in 0.5, 1.5, 3, 6, 24 hours after treatment. The cell proliferation and cell activity was also evaluated at 2 and 7 days after 1 minute exposure, twice a day. The cell morphology was similar between the Lipomyces smkeyi KSM 22 glucanhydrolase groups and control group during the incubation periods, while most fibroblasts remained as round cell regardless of incubation time in the chlorhexidine group. The numbers of the attached cells in the glucanhydrolase groups were comparable to that of control and significantly higher than the chlorhexidine group. The numbers of the proliferated cells in the glucanhydrolase groups at 7 days of incubation were comparable to the control group and higher than the chlorhexidine group. The cell activity in glucanhydrolase groups paralleled with the increased cell number by attachment and proliferation. According to these results, Lipomyces starkeyj KSM 22 glucanhydrolase has little harmful effect on attachment and proliferation of human gingival fibroblasts, in contrast to 0.1% chlorhexidine which was cytotoxic to human gingival fibroblasts. Therefore this glucanhydrolase preparation is considered as a safe and promising agent for new mouthwash formula in the near future.